Technical Field
The present invention relates to a communication system which constructs a communication network using a hopping pattern designated in a router advertisement between a wireless communication device that transmits the router advertisement that designates the hopping pattern of channel hopping and an opposite party communication device that receives the router advertisement.
Related Art
In ISA100.11a, provisioning means an engineering for performing initial setting of a network parameter and a security parameter in order to connect a wireless device to a wireless infrastructure. As the provisioning that is prescribed as the specification of ISA100.11a, there is OTA (Over The Air) provisioning that is performed using the ISA100.11a protocol, and the OTA provisioning is classified into handheld OTA provisioning and tool-less OTA provisioning.
In the handheld OTA provisioning, initial setting of a wireless device (DBP: Device Being Provisioned) is performed on an ISA100.11a wireless subnet (provisioning network) that is physically isolated from an ISA100.11a wireless infrastructure (target network) using a handheld PD (Provisioning Device) that is a dedicated device. The wireless device (DBP) is connected to the target network after the provisioning is performed in the provisioning network.
Hereinafter, the procedure of the handheld OTA provisioning will be described.
(1) Step 1
A handheld PD 101 including a routing device function periodically broadcasts a router advertisement. A circle shown in FIG. 8A expresses a range in which the wireless device (DBP) 102 can receive the router advertisement. The range in which the router advertisement can be received corresponds to the provisioning network.
(2) Step 2
In the router advertisement, a network parameter that is required for the wireless device (DBP) 102 to connect to the provisioning network is stored, and the wireless device (DBP) 102 can acquire the network parameter through receiving the router advertisement, and connect to the provisioning network. Further, an actual connection process includes a plurality of transactions.
(3) Step 3
If the connection of the wireless device (DBP) 102 to the provisioning network is completed, the handheld PD sets the network parameter and the security parameter for connecting the wireless device (DBP) 102 to the target network. Further, an actual setting process includes a plurality of transactions.
In ISA100.11a, communication is performed by TDMA (Time Division Multiple Access) using channel hopping, and in step 2, the handheld PD notifies the wireless device (DBP) of the hopping pattern to be used in practice. This hopping pattern is selected from the five default channel hopping patterns predefined in ISA100.11a.
The channel hopping is managed at absolute time on the basis of a zero point of international atomic time, and the router advertisement that is transmitted by the handheld PD includes a hopping offset at the zero point of the international atomic time as a parameter. Further, the hopping is performed at equal durations, and the router advertisement includes respective hopping durations as a parameter.
In ISA100.11a, it is suggested that the handheld PD transmits the router advertisement on channel 15 or channel 25 of IEEE802.15.4. The wireless device (DBP) receives the router advertisement by scanning channel 15 or channel 25 at startup, and synchronizes the hopping pattern of the wireless device (DBP) with the handheld PD by acquiring the hopping pattern, offset, and durations being used.
Further, definition of channel hopping such as default hopping pattern is described at Paragraph 9.1 (P.249 to P.314) of Non-Patent Document 1, advertisement of the channel hopping setting being used in a wireless subnet in the router advertisement is described at Paragraph 9.3 (P.317 to P.338), and definition of provisioning is described in Chapter 14 (P.666 to P.693).